milos-linux/net/vmw_vsock
Raf Dickson c05fa14db4 vsock/vmci: fix sk_ack_backlog leak on failed handshake
When vmci_transport_recv_connecting_server() returns an error,
vmci_transport_recv_listen() calls vsock_remove_pending() but never
calls sk_acceptq_removed(). This leaves sk_ack_backlog incremented
permanently.

Repeated handshake failures (malformed packets, queue pair alloc
failure, event subscribe failure) cause sk_ack_backlog to climb
toward sk_max_ack_backlog. Once it reaches the limit the listener
permanently refuses all new connections with -ECONNREFUSED, a
silent denial of service requiring a process restart to recover.

The two existing sk_acceptq_removed() calls in af_vsock.c do not
cover this path: line 764 checks vsock_is_pending() which returns
false after vsock_remove_pending(), and line 1889 is only reached
on successful accept().

Fix by balancing sk_acceptq_added() with sk_acceptq_removed() on
the error path.

Fixes: d021c34405 ("VSOCK: Introduce VM Sockets")
Cc: stable@vger.kernel.org
Signed-off-by: Raf Dickson <rafdog35@gmail.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20260526104356.469928-1-rafdog35@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-06-04 13:08:02 +02:00
..
af_vsock.c vsock: keep poll shutdown state consistent 2026-05-22 11:27:57 -07:00
af_vsock_tap.c
diag.c sock_diag: add module pointer to "struct sock_diag_handler" 2024-01-23 15:13:54 +01:00
hyperv_transport.c vsock: keep poll shutdown state consistent 2026-05-22 11:27:57 -07:00
Kconfig Drivers: hv: Add CONFIG_HYPERV_VMBUS option 2025-10-01 00:00:42 +00:00
Makefile vsock: support sockmap 2023-03-29 08:19:38 +01:00
virtio_transport.c vsock: add G2H fallback for CIDs not owned by H2G transport 2026-03-12 10:59:36 +01:00
virtio_transport_common.c vsock/virtio: bind uarg before filling zerocopy skb 2026-05-29 12:38:00 -07:00
vmci_transport.c vsock/vmci: fix sk_ack_backlog leak on failed handshake 2026-06-04 13:08:02 +02:00
vmci_transport.h vsock: Remove unused function declarations 2023-07-31 14:41:08 -07:00
vmci_transport_notify.c vmci/vsock: check SO_RCVLOWAT before wake up reader 2022-08-23 10:43:12 +02:00
vmci_transport_notify.h vsock: remove include/linux/vm_sockets.h file 2019-11-14 18:12:17 -08:00
vmci_transport_notify_qstate.c vmci/vsock: check SO_RCVLOWAT before wake up reader 2022-08-23 10:43:12 +02:00
vsock_addr.c net: Convert proto_ops connect() callbacks to use sockaddr_unsized 2025-11-04 19:10:32 -08:00
vsock_bpf.c net: remove addr_len argument of recvmsg() handlers 2026-03-02 18:17:17 -08:00
vsock_loopback.c vsock: add netns support to virtio transports 2026-01-27 10:45:38 +01:00